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Thorium Dioxide Hazard Summary Identification

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Thorium Dioxide Hazard Summary Identification Common Name: THORIUM DIOXIDE CAS Number: 1314-20-1 DOT Number: UN 2909 RTK Substance number: 1856 DOT Hazard Class: 7 (Radioactive) Date: May 1998 Revision: May 2007 ------------------------------------------------------------------------- ------------------------------------------------------------------------- HAZARD SUMMARY * Thorium Dioxide can affect you when breathed in and from your employer. You have a legal right to this may be absorbed through the skin. information under the OSHA Access to Employee * Thorium Dioxide is a CARCINOGEN--HANDLE WITH Exposure and Medical Records Standard (29 CFR EXTREME CAUTION. 1910.1020). * Thorium Dioxide is broken down in the body into * If you think you are experiencing any work-related health radioactive substances. problems, see a doctor trained to recognize occupational * Thorium Dioxide may be contaminated with radioactive diseases. Take this Fact Sheet with you. Thorium. This could contaminate work surfaces and provide an ongoing radiation hazard and increasing future WORKPLACE EXPOSURE LIMITS risk of cancer. Exposure to radioactive materials is regulated by the Nuclear * Exposure can reduce the ability of the bone marrow to Regulatory Commission (NRC) and OSHA. Refer to the make white blood cells. NRC Standards for Protection Against Radiation Occupational * Low repeated exposures may scar the lungs. Dose Limits (10 CFR 20.1201) and the OSHA Ionizing * Exposure may damage the liver and kidneys. Radiation Standard (29 CFR 1910.1096). * After exposure, some Thorium Dioxide is retained in the bones and other body organs for many years. * Thorium Dioxide is a CARCINOGEN in humans. There may be no safe level of exposure to a carcinogen, so all IDENTIFICATION contact should be reduced to the lowest possible level. * It should be recognized that Thorium Dioxide can be Thorium Dioxide is a heavy, white, crystalline (sand-like) powder. It is used in ceramics, in nuclear fuels, as a catalyst, absorbed through your skin, thereby increasing your and in electrodes for arc welding. exposure. REASON FOR CITATION WAYS OF REDUCING EXPOSURE * Thorium Dioxide is on the Hazardous Substance List * Enclose operations and use local exhaust ventilation at the because it is cited by DOT, NTP, DEP, IARC and EPA. site of chemical release. If local exhaust ventilation or * This chemical is on the Special Health Hazard Substance enclosure is not used, respirators should be worn. List because it is a CARCINOGEN. * A regulated, marked area should be established where * Definitions are provided on page 5. Thorium Dioxide is handled, used, or stored. * All processes involving Thorium Dioxide should be HOW TO DETERMINE IF YOU ARE BEING mechanized, enclosed or automated. * When working with small quantities of Thorium Dioxide, EXPOSED use in a glove box. The New Jersey Right to Know Act requires most employers * Wear protective work clothing. to label chemicals in the workplace and requires public * Wash thoroughly immediately after exposure to Thorium employers to provide their employees with information and Dioxide and at the end of the workshift. training concerning chemical hazards and controls. The * Post hazard and warning information in the work area. In federal OSHA Hazard Communication Standard (29 CFR addition, as part of an ongoing education and training 1910.1200) requires private employers to provide similar effort, communicate all information on the health and training and information to their employees. safety hazards of Thorium Dioxide to potentially exposed workers. * Exposure to hazardous substances should be routinely evaluated. This may include collecting personal and area air samples. You can obtain copies of sampling results THORIUM DIOXIDE page 2 of 6 This Fact Sheet is a summary source of information of all Any evaluation should include a careful history of past and potential and most severe health hazards that may result from present symptoms with an exam. Medical tests that look for exposure. Duration of exposure, concentration of the substance damage already done are not a substitute for controlling and other factors will affect your susceptibility to any of the exposure. potential effects described below. -------------------------------------------------------------------- ----- Request copies of your medical testing. You have a legal right to this information under the OSHA Access to Employee HEALTH HAZARD INFORMATION Exposure and Medical Records Standard (29 CFR 1910.1020). Acute Health Effects Mixed Exposures The following acute (short-term) health effects may occur * Because smoking can cause heart disease, as well as lung immediately or shortly after exposure to Thorium Dioxide: cancer, emphysema, and other respiratory problems, it may worsen respiratory conditions caused by chemical exposure. * Exposure can reduce the ability of the bone marrow to Even if you have smoked for a long time, stopping now will make white blood cells. reduce your risk of developing health problems. * Because more than light alcohol consumption can cause Chronic Health Effects liver damage, drinking alcohol can increase the liver The following chronic (long-term) health effects can occur at damage caused by Thorium Dioxide. some time after exposure to Thorium Dioxide and can last for months or years: WORKPLACE CONTROLS AND PRACTICES Cancer Hazard Unless a less toxic chemical can be substituted for a hazardous * Thorium Dioxide is a CARCINOGEN in humans. It has substance, ENGINEERING CONTROLS are the most been shown to cause lung cancer. effective way of reducing exposure. The best protection is to * Many scientists believe there is no safe level of exposure to enclose operations and/or provide local exhaust ventilation at a carcinogen. Such substances may also have the potential the site of chemical release. Isolating operations can also for causing reproductive damage in humans. reduce exposure. Using respirators or protective equipment is less effective than the controls mentioned above, but is Reproductive Hazard sometimes necessary. * According to the information presently available to the New Jersey Department of Health and Senior Services, Thorium In evaluating the controls present in your workplace, consider: Dioxide has not been tested for its ability to affect (1) how hazardous the substance is, (2) how much of the reproduction. substance is released into the workplace and (3) whether * Because Thorium Dioxide gives off very dangerous harmful skin or eye contact could occur. Special controls radiation, it has the potential for causing reproductive should be in place for highly toxic chemicals or when damage in humans. significant skin, eye, or breathing exposures are possible. Other Long-Term Effects In addition, the following controls are recommended: * Low repeated exposures may scar the lungs. * Exposure may damage the liver and kidneys. * Where possible, automatically transfer Thorium Dioxide * After exposure, some Thorium Dioxide is retained in the from drums or other storage containers to process bones, lymph system, lungs and other body organs for containers. many years. * Specific engineering controls and personnel monitoring are required by the NRC Standards for Protection Against MEDICAL Radiation (10 CFR 20) and the OSHA Ionizing Radiation Standards for Protection Against Radiation (29 CFR 1910.1096). Also check specific state regulations. Medical Testing Before beginning employment and at regular times after that, Good WORK PRACTICES can help to reduce hazardous the following are recommended: exposures. The following work practices are recommended: * White blood cell count * Workers whose clothing has been contaminated by * Lung function tests Thorium Dioxide should change into clean clothing * Consider periodic chest x-ray for persons with potentially promptly. high or repeated lower exposure. * Do not take contaminated work clothes home. Family members could be exposed. If symptoms develop or overexposure is suspected, the * Contaminated work clothes should be laundered by following are recommended: individuals who have been informed of the hazards of exposure to Thorium Dioxide. * Liver and kidney function tests * Eye wash fountains should be provided in the immediate work area for emergency use. THORIUM DIOXIDE page 3 of 6 * If there is the possibility of skin exposure, emergency * Engineering controls must be effective to ensure that shower facilities should be provided. exposure to Thorium Dioxide does not occur. * On skin contact with Thorium Dioxide, immediately wash * At any exposure level, use a NIOSH approved supplied-air or shower to remove the chemical. At the end of the respirator with a full facepiece operated in a pressure- workshift, wash any areas of the body that may have demand or other positive-pressure mode. For increased contacted Thorium Dioxide, whether or not known skin protection use in combination with an auxiliary self- contact has occurred. contained breathing apparatus operated in a pressure- * Do not eat, smoke, or drink where Thorium Dioxide is demand or other positive-pressure mode. handled, processed, or stored, since the chemical can be swallowed. Wash hands carefully before eating, drinking, QUESTIONS AND ANSWERS applying cosmetics, smoking, or using the toilet. * Employees exposed to ionizing radiation should be Q: If I have acute health effects, will I later get chronic provided with personal monitoring equipment such as film health effects? badges or pocket dosimeters. A: Not always. Most chronic (long-term) effects result from * Use
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